Improvement in hot-air engines



2 Sheets-Shet 11' A. K. RIDER. HOT AIR ENGINE.-'

No. 111,087. Patented Jan. 17, 1871 7 Sheet I 2 Sheets A. K. RIDER.

HOT AIR ENGINE. 1N0.111,087 Patented Jan.17, 1871.

m mama m-zns ca. PHOTO-M1340"WAS new one ALEXANDER RIDER, for NEW YORK, N Y.,-ASSIGNO R TO HIMSELF, cease LIUS n. DELA'MATER, AND eEoneE'H. REYNoLDs,oF SAME PLACE.

Letters Patent, No. 111,037, dated January 17,1871.

I MI-R'OVENIEN'I'."llil HOT-AIR ENGINES.

The Schedule referred. to in these Letters PM and flaking partial the same.

To all whom it'hiay concern that class of air-engines described in the patents granted by the'jUnitedStates'to John Ericsson, dated July 31, 1855, and December 14,1858. g In this class of engines, which I. will term the aspirating or-Ericsson engine, twopistons are employed in one cylinder, which' performs the double oflice'of air-pump and power-cylinder. 'The objects of my invent-ion arepiston engine with an "internal .or closed furnace, in which the'air is heated bypassing throughor over the fire, thereby greatly increasing the power and efficiency of this classof engines as'hitherto constructed. Second, to induce the peculiar motions or the inner or shitting .piston'by simple, inexpensive, and irery 'eflicient' mechanisma r 1 1 Third, to make the engine reversible, so that it may bc-applied as a transportation motor, by means of'a mre change of position of certain parts, with suitable changes of valve'rnotion. p a

Fourth, to more perfectly-regulate the speed of the engine under varying conditions of load without waste of fuel. This is done by a "peculiar valve and pass-- ages peculiarly arranged to be controllcdthereby, the

. valve being adapted to be operated by a governor.

Passing lightly over those partsoi' the machine which havebeen long knownnnd in common use, I

will .devote attention mainly to the features which I believe to be new and peculiar to my engine, and will describe what I consider the best-means of putting njy invention into efi'e'ct.

specification.

Figure 1 is a central -vertical section, showing in a clear light the construction and the relation to each other of the several parts. The section shows but one of therods which operate the shifter, but it will be understood that there are'two, the other being this side of the plane of section. I p

. Figure/5 shows a modification which involves some of the novel points. The remaining figures show details enlarged.

Figure 2 shows the regulating valve in position to.

increase the fire, and thns indirectly to increase the speed of the engine.

Figure 3 shows the same valve in position to slack en the fire, and

ingto the cylinder.

Figure 4 shows the saine valve imposition to not only slacken the fire, but also to directly retard the engine by throttling it. I Y

The diagram at the/side ot fig. 5 isan indicator diagram, taken onone of myengines. The severallines with the brief explanation marked thereon may be of serviceto those familiar with this mode of ascertain ing the conditions-at different points; a

Similar letters of referenccindicate corresponding parts in all the fignres' B is the cylinder, whichalso serves as the air-pump, as above stated. It is formed in the usual manner,

attached below 'to the furnace casing B by flanges and bolts.

Abov' the 'y-l'inder s arr-mung, A,which earl-res I, 'thepihow-block,and'slides. Firshtdcomhihe this-class of aspiratin'gor'donblewith leather or other suitable matcrial to inalieilh, tight. 1 M is a piston, which term the inner or shifting piston, fitting closely, but easily in the cylinder, and

prolonged downward toward the fire, to prevent the heatacting injnriously 'on the-packing of the main piston. a I

N is a check-valve, to prevent the air from. return 0 is a pipe leading'to the furnace, whichlis for the purpose of carrying dowtr'the air. Bis the regulating valve; and

0 is the furnace.

' he changing piston or shifter M is connected by two rods, J, passing through the main piston E to the cross-head I, which latter work's inslides provided'in .thc framing A, and receives motion from connection to thc ciank'and main piston, as will be presently ex V p plained. 4 The accompanying drawing Iorms' a partof this p The connecting-rod G is of peculiar conformation. Between the main'piston E and the crank-pin it is a direct connection, but it is provided with-an offset, G, which carries the point of attachment g, by which the upper connect-ing-link Htransrnits motion to the cross-head I, and through the piston-rods J to thcinner or shiftingpiston M. v V The position of this offset G and point of attach.- ment yl na-y be varied within widelimits, and yet pro duce very nearly the required effect. It may be be yond or above the cra -11k-pi n,-as. shown, or between the piston and crank-pin, orit may be nearer to or further from the line of the connecting-rod proper, or it may form a right angle with the other two hearings on the connecting-rod; these proportions depending on thostroke given to tho shift-ing piston, the length a 'piston',-, ivhich I lerln thcflnurin piston, in,

(of themunectiois and thc relative motions required When it is necessary to'makc thcengine reversible,

as for purposes oflocomotiou or navigation, the offset is duplicated, one being formed on each side of the connecting-rod.

lhe offsets G (i may then be connected as shown in fig. 1., by a link-slot, 'G", as shown, in such a manner that the upper connecting-link H can be shifted at its lower end to the reverse side, opposite to its former point ofattachmcnt, and thus reverse the engines motion, the va rcspondingly changed, as willbe understood. r

This form-is shown in fig. 1. v I

For stationary engines,'howevcr, but one ofi'set and point of attachment is necessary, as shown in fig.-5.

In order to obtain the best result, the shifting piston or shifter M'shonld start; to come out or toward the main piston considerably in advance of the termination of the inward stroke of the latter, so as be nearly or quite in contact with the main piston at the commencement of its up or outward stroke, and should remain close to the main piston during" nearly all of "the up or outward stroke, a. little before the end of which the 'shiftershould rapidly descend,'so1 as to reach its lowest or extreme inward position alittlcbefore.

the half'of the inward stroke of the. main piston has been performed. The. arrangement of parts described. fulfils these conditions. I

In engines of this class hitherto constructed, any lead on the shifting p ston was considereddetrimental, and avoided as much as possible, only a very small amount beingpcrmitted, on account of rendering the I motion more easy at the end of the stroke.

In my engine, on the contrary, it is purposely made as much ,as possible with the simplewconnections adopted, the cheat of which may be seen on the indicatorcard at the points a l), where the rise above the Marriott, curve appe. rs.

The lower end of H'may beconnected to either end of the link G, and may be firmly held in either end.

by means of a suitable key orpinching-screw, or other suitable means. The lower end of H is shilted from one end to the other cnd'of the'link G, to. cause the;

engine to revolve in the opposite direction. In other words, the engine is reversed by 'changing the union of the connection H from one end to the other of the link G, and making correspondingchanges. by ordinary or suitable means, in the positions of the eccentrics or other'nicans which operate the valves, as will be readily understood.

it will be observed that the lower end of the link H, operated by a pin, g, traverses in a circuit, the center of which is one side of the central line of the engine, and that the central line is nearly or quite tangential to said circuit. I ascribe to this relation much of the excellence of this motion.

, (narration. v

Supposing the connection H to be adjusted as represented, and efliciently confined in the end of the link (3*, so that it is free to turn upon a pin, g, temporeally but firmly fixed at that point, the crank .is ready to revolve in the direction indicated by the arrow. Supposing the engine to be started by hand, or by some other power applied for the purpose, during each revolution of the crank D and consequent descent and iise of the main piston 1d, the under member, which 1 call 'a shifter, and which does notnecessarily fit tight in the cylinder, descends further and morerapidly, caus ng an influx ot' cool atmospher c air through the wi es 0 in the piston E. The exhaust valve passageliis open during the early portion of this descent. After the shifter has descended to its overthe fire andbe heated.

lvemotionf, ,dcc, being cor lowest p osirtiio mthe pistou'E follows it, to a smaller extent; and, the sliiftcr rises' to meet the piston, it reduces the space between; the shifter M andthe piston E, and causes the main body of the air which is inclosed between, the shifter and the pistoirto be driven downward through the self-actingvalvehl, and through the connected passage 0, to pass through or The passage of thiscool air through, or in contact with, the tire, raises its temperature andincreases its pressure very greatly.

Now the shifter havin' risen until it is nearl in con-' 7 D.

' tact witli the piston, the latter commences to rise,

and both move upward with a motion very nearly coincident. It is-inthis'portion of the -revolution that the power of the heated air is given off throughthe;

cranial) to the shaft 1) and its connections. A sufficientmomentum is storefd in the flywheel, in case of a single engine, to enable it toperform the remain'-.

der of its revolution, as will be readily understood.

The passage 0 communicates, through the peculiarvalve '1, with two passages 0" 0*, which lead, the former under -the fire-grate, and the latter above it.

The 'valve P is capable of turning easily upon itsaxis, and,in case it is adjusted to cause the compressed air'to pass through the ,passage 0, it blows-the fire and urges it. In case it is adjusted so as to close the passage 0 and open the passage 0,it causes the com-- pressed air to flow into the furnace above the fire, and

in this condition its influence in urgingthe fire is almost inapprecia-ble. Under ordinary conditions the]' valve will be adjusted so that a portion of the air will flow through thepassage O and urge the fire, while another portion will flow, through the passage 0" The relative proportion may bevaried by changing the po-. sit-ion otthc valve 1 and thus the fire may be increased ornot by'the' action of the engines, or it may bciu'ged in varying measures at pleasure .The construction and arrangement of my j valve lP allows the application of a-governor, (not represented,) which maybe driven by a band from the main shaft D of theengine, and generate a. motion corresponding thereto. The action required is precisely that of'theordinary.governor, and the connection therefrom to this valve 1; may be of any ordinary or suitable charactor, and willrcquire no special detailed description.

' There is a peculiarity, however, about the valve 1,

which, whether operated by thegovernor'or by hand, i

causes it to perform an important fuuctionin addition to that before explained. Its form and its relation to' the ports is such, that after it has been turned in theproper direction to a sufiicient extent to shut off the air from the channel 0, and has thus caused all the air to 'flowtbrough the channel 0, under the conditions which are the least comlneive to the-urging of the fire, a still further motion in the same direction 'will bring into play a new agency for still further or more rapidlyredncing the velocity of the engine. The valve will, under such extreme conditions, partially throttle or obstruetthe flow of air downward through the passage 0. This position of the valve, and this condition of that portion of the mechanism, is clearly shownin fig. 4.

In case of'the breaking of a belt, or any othcr'sudden relief of the engine from resistance when laboring hea ily and carrying-a very hot fire, the engine is liable to attaina dangerously high speed. The shutting off of the air from the passage 0 under such circum stances will in time reduce the heat of the furnace, and thus restore the proper conditions; but, in the'interim, damage may be done; My valve P prevents this by checkingthemotiou of .the air through the passage 0, under these extraordinary circumstances. In case the valve is operated by a governor, this action will result automatically.

' Lhave omitted to describe the fire-brick lining of the furnace, and many details which will be readily undelstood by those familiar with this branch of engineering, Among these is the exhaust-valve, the passage to which is represented by R.

Although my engine works, preferably, by exposing the fair directly to. the fire, or, in other words, forcing it through the flre and causing it to support combustion, some of its novel features may be made availa-' ahlei if theair. is heated by an external fire-hy means of heat transmitted throngh metallic or other suitable surfaces. v

I claim as n:y.invention--- '1. The aspirating engine, having two pistons E and M, workingin the same cylinder A, in combination with the'internal or closed furnace O, and with passages for conducting the air from the cylinder tothc furnace and again to the cylinder, as herein specified;

2. The connecting-rod G, constructed with an olfsct,.arrying the attachment of the upper link H,-

Witnesses:

.Tnonss D. Srn'rsox (l. O. Ln'mes, -A. Honmmzm. 

